DECEMBER 2, 1996: The Pleiades
- Around 8-9 p.m., look east to view the three belt stars
of Orion, the Hunter, pointing up nearly vertically from the horizon. Following
them will lead to Aldebaran and the Hyades described in last week’s StarWatch.
Continue past the Hyades, to a fuzzy patch of light called the Pleiades or Seven
Sisters. Often misrepresented for a constellation, the Pleiades star cluster, like
the Hyades, are really part of Taurus, the Bull. The Pleiades are about 425 light
years distant, thus making their angular size considerably smaller than the Hyades.
DECEMBER 9, 1996: Geminid Meteors
- Look due west, at 6 p.m. for Comet Hale-Bopp. H-B will
be about 1-2 binocular fields above an unobstructed horizon. The moon will be at the
same height as the comet on the 12th, but H-B will be about 3-4 binocular fields to
the right. On Friday the 13th, look eastward for abundant meteors after 9 p.m. They
will appear to diverge from the area around two bright stars, Caster and Pollux. These
famed Geminid meteors treat skywatchers to an annual show of between 20-60 meteors/hour
on this date. Local light pollution will suppress this number to about 20 meteors/hour
DECEMBER 16, 1996: Winter Solstice
- The moon appears to the right of Saturn on Monday, above
the ringed world on Tuesday, and to Saturn’s left by Wednesday. Winter solstice occurs
on Saturday December 21st at 9:06 a.m., marking the shortest day of the year. For
the Lehigh Valley, the sun will rise in the southeast at 7:22 a.m. Nine hours, 16
minutes later, at 4:38 p.m., it will set in the southwest. The sun will be only 26
degrees above the horizon at local noon. These days are the times of the long shadows.
DECEMBER 23, 1996: Winter Stars Rise
- On Monday the 23rd look towards the southeast about 10 p.m.
The nearly full moon will be encircled by a group of dazzling stars from a half dozen
winter constellations. Starting below the moon at the six o’clock position, there is
the brightest star of the nighttime sky, Sirius (Canis Major) at 7:30, Procyon
(Canis Minor) at 9:00, two stars, Pollux (lower) and Caster (Gemini) at 11:00, Capella
(Auriga) at 2:00 and closest to the moon, Aldebaran (Taurus) and at 4:00, bluish Rigel
(Orion). Repeat this exercise several nights later without the moon. Start with Sirius.
DECEMBER 30, 1996: Orion's Belt
- About 8 p.m. in the east are the three belt stars of Orion,
the Hunter: Mintaka (top), Alnilam, and Alnitak. Using binoculars you will discover
they all shine with a bluish glow. These luminaries are all very distant from earth,
about 1600 light years. They are consuming their hydrogen fuel 10’s of thousands of
times more rapidly than the sun. Consequently, they will only shine for a few 10’s of
millions of years. Compare this to the less spectacular yellow sun, which is halfway
through its 10 billion year existence. To be continued...